Miaow-miaow on trial: Truth or trumped-up charges?

"Legal high kills two teens," cries the Daily Express. "Legal drug teen ripped his scrotum off," roars The Sun. A steady stream of stories in the UK media about a little-known "legal high" variously called mephedrone, plant food, miaow-miaow or m-cat reached fever pitch this month. Newspapers, teachers and parents demanded an immediate ban. Les Iversen, the UK government's chief drugs adviser, recommended that the drug be put in the same class as amphetamines, making possession punishable by five years in prison. The government is likely to announce plans for an emergency ban that could be enacted within days.

This knee-jerk response may be unsurprising, but what is far from clear is whether criminalisation is the right thing to do to reduce drug harms. While mephedrone has been implicated in at least 27 deaths in the UK, it has been confirmed present in just 11 of these cases and at the time of writing found to be a contributing factor in just one. There is virtually no published research on how the substance affects the human body. Iversen himself recently admitted that "there is no data on toxicity that I could find". Intrigued at the rush to action despite the lack of hard evidence, I decided to try to sort the facts from the frenzied speculation (see "Miaow-miaow myths").

Khat to chat

Mephedrone is a synthetic analogue of the herbal amphetamine cathinone, found naturally in the leaves of the khat plant, Catha edulis. Chewing khat leaves is a popular ritual in some east African communities. Mephedrone, or 4-methylmethcathinone, is part of a family of synthetic cathinones created to mimic khat's stimulant properties.

Its precise origins are unclear, though early reports suggest it was being supplied by an Israeli legal high seller called Neorganics as far back as 2007. Fearing it would affect army conscripts, the government there banned mephedrone later that year.

Around that time, mephedrone began appearing on internet chat forums, and the drug seems to have spread rapidly since then: significant use is now reported in Sweden, Finland, the UK, Ireland and Australia. The vast majority of mephedrone is produced in China and sold to dealers for between £2500 and £4000 per kilogram. No one knows how much is being exported globally.

Substance displacement

What is clear is that a lot of people are using it. An online survey of 2222 readers of British clubbing magazine Mixmag, published in January, suggested that mephedrone had become the fourth most popular drug among the readers of the website after cannabis, ecstasy and cocaine. Thirty-four per cent of respondents said they had taken it in the previous month. "We've never had a drug become so popular so quickly about which we know so little," says Fiona Measham, a criminologist at Lancaster University in Bailrigg and member of the UK government's Advisory Council on the Misuse of Drugs (ACMD).

The emergence of legal highs should come as no surprise. "When restrictions are placed on the supply of drugs and demand remains high you get substance displacement," says Danny Kushlick of Transform, a UK think tank opposed to drug prohibition.

Key to mephedrone's extraordinary rise in Europe has been the recent success of crackdowns on ecstasy and cocaine supply: there was a drop in purity of cocaine seized by the police in England and Wales from over 60 per cent in 1999 to 22 per cent in 2009, and about half of ecstasy pills seized last year contained no MDMA, ecstasy's active ingredient.

"When you're buying [controlled] drugs on the street you have no idea what you're getting. You can spend £100 and get nothing," a regular user of mephedrone told me. The 37-year-old, who wishes to remain anonymous, switched from taking ecstasy and speed about two years ago. "With mephedrone you can walk into a head shop or go online and feel safe going back to the same supplier."

"Plant food"

I decided to see for myself how easy it would be to get hold of mephedrone. A quick online search for "mephedrone" revealed hundreds of websites. Moments later I was on the phone ordering a special delivery of 5 grams of "plant food" for £60, plus £25 for a courier service. Two hours later a courier called from outside my house. He insisted I sign a disclaimer saying I knew mephedrone was not for human consumption, then handed over a brown, padded envelope. Inside was a small plastic bag half-full of white powder.

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